Osteotomy protective cover

ABSTRACT

A cover for use in protecting a resected surface of a long bone for use in joint arthroplasty includes a body, a plurality of independently moveable members moveably attached to the body, two of the plurality of independently movable members configured to move linearly with respect to the body along a first plane and along a first axis, the body and the plurality of independently moveable members defining a first periphery of the cover along the first plane in one configuration which is smaller than, and encompassed by, a second periphery of the cover along the first plane in a second configuration, and a lip fixedly extending downwardly along an outer radial periphery of one of the body and the plurality of independently moveable members in a direction not co-planar with the first plane.

This application is a divisional of application Ser. No. 14/458,521,filed Aug. 13, 2014, which issued as U.S. Pat. No. 9,925,065 on Mar. 27,2018, which in turn is a divisional of application Ser. No. 11/529,885,filed on Sep. 29, 2006, which issued as U.S. Pat. No. 8,821,496 on Sep.2, 2014, the disclosures of which are each incorporated herein byreference in their entirety.

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to the field of orthopaedics,and more particularly, to an instrument for use in arthroplasty.

BACKGROUND OF THE INVENTION

The present invention relates to implantable articles and methods ofimplanting such articles. More particularly the invention relates to abone prosthesis, prosthesis trial, instrument and method for implantingthe same.

There are known to exist many designs for and methods for implantingimplantable articles, such as bone prostheses. Such bone prosthesesinclude components of artificial joints, such as elbows, hips, knees andshoulders.

One such implantable prosthesis is a shoulder prosthesis. During thelife time of a patient, it may be necessary to perform a total shoulderreplacement procedure on a patient as a result of, for example, diseaseor trauma, for example disease from osteoarthritis or rheumatoidarthritis. Currently, implantable shoulder prostheses include totalshoulder prostheses and humeral head resurfacing replacement, as well asother devices. In a total shoulder replacement procedure, a humeralcomponent having a head portion is utilized to replace the natural headportion of the upper arm bone or humerus. The humeral componenttypically has an elongated intermedullary stem, which is utilized tosecure the humeral component to the patient's humerus. In such a totalshoulder replacement procedure, the natural glenoid surface of thescapula is resurfaced or otherwise replaced with a glenoid componentthat provides a bearing surface for the head portion of the humeralcomponent.

During arthroplasty, for example, a total shoulder replacementarthroplasty, the articulating surface, for example, the humeral head isremoved as a first step, leaving an exposed resected surface. The stepsin performing humeral joint arthroplasty includes having the surgeonream the glenoid cavity. If the exposed bone is not well protected whilethe surgeon reams the glenoid cavity surface, or at other steps in thearthroplasty, the resected humerus may be damaged, resulting inunnecessary bone loss. The use of less invasive surgical proceduresreduces the visibility to the resected surface and can lead to increaseddamage to the resected surface of the bone.

Attempts have been made to protect the resected surface of long bone.For example, osteotomy covers have been provided to be placed on thelong bone. The prior art osteotomy protectors are round discs. The useof multiple sizes of the round discs are required to accommodate thewide variety in the size and shape of the resected surface of the longbone.

With only a few fixed round sizes, the surgeon is not able to cover therange of patient size necessary for full protection of the resected longbone. If the fixed sized protector is slightly smaller than theosteotomy surface, the outer cortical bone at the resected surface ofthe bone may be damaged or loss of bone may occur. If the fixed sizedprotector is slightly larger than the osteotomy surface, the protectormay interfere with soft tissue surrounding the humerus or obstruct thesurgeon from the preparing the glenoid. Such obstruction is morepronounced for minimally invasive surgeries where access and view of thesurgical sight is more problematic.

The present invention attempts to overcome at least some of theaforementioned problems.

SUMMARY OF THE INVENTION

According to one embodiment of the present invention, a cover for use inprotecting a resected surface of a long bone for use in jointarthroplasty is provided. The cover includes a generally planar portionhaving opposed generally parallel first and second surfaces defining aperiphery extending from the first surface and the second surface. Thecover also includes a lip extending from the first surface at theperiphery of the planar portion in a direction not planar with thegenerally planar portion.

According to another embodiment of the present invention there isprovided a cover for use in protecting a resected surface of a long bonefor use in joint arthroplasty. The cover includes a body and a membermoveably attached to the body along a first plane. The body and themember define a first periphery of the cover when the body and themember are in a first position with respect to each other and define asecond periphery of the cover when the body and the member are in asecond position with respect to each other. The second periphery isgreater than the first periphery.

According to yet another embodiment of the present invention there isprovided an instrument set for use on a long bone in joint arthroplasty.The instrument set includes a cover for use in protecting a resectedsurface of a long bone. The cover has a body and a member moveablyattached to the body along a first plane. The body and the member definea first periphery of the cover when the body and the member are in afirst position with respect to each other and define a second peripheryof the cover when the body and the member are in a second position withrespect to each other. The second periphery is greater than the firstperiphery. The instrument set also includes a broach for preparing acanal in the long bone.

According to still another embodiment of the present invention there isprovided a kit for use on a long bone in joint arthroplasty. The kitincludes a cover for use in protecting a resected surface of a longbone. The cover has a body and a member moveably attached to the bodyalong a first plane. The body and the member define a first periphery ofthe cover when the body and the member are in a first position withrespect to each other and define a second periphery of the cover whenthe body and the member are in a second position with respect to eachother. The second periphery is greater than the first periphery. The kitalso includes a broach for preparing a canal in the long bone and animplant stem for implantation in to the canal of the long bone.

According to yet another embodiment of the present invention there isprovided a method for protecting the resected surface of a long bone foruse in joint arthroplasty. The method includes the steps of resectingthe long bone and providing a cover including a first portion and asecond portion the second portion moveable with respect to the firstportion. The method also includes the steps of placing the cover overthe resected end of the long bone, adjusting the cover to fit theresected end of the long bone, and securing the cover to the resectedend of the long bone.

The cover of the present invention may be used on a resected humerus,but it should be appreciated that such a cover or protector may also beused to protect other long bones, for example a femur. The protectorincludes a circular body and size adjusting plates that move withrespect to the body. For example, four equally spaced size adjustableplates may be used. Each of the four plates can be adjusted outward fromthe body, increasing the overall size of the protector and providingmore coverage of the newly resected exposed bone. The moving platesallow protection of multiple size humeri and varying patient anatomy.

The protector also may include a protective lip extending downwardlyfrom the plate. The lip prevents the surgeon from damaging the humeruswhile retracting to expose the proximal resected and exposed bone. Theadjustable osteotomy protector allows for protection of multiple humeralsizes and varying patient anatomy. The osteotomy protector also providesa protective lip which prevents the surgeon from damaging the humerus toexpose the proximal humerus or glenoid while performing the humeralarthroplasty, including exposing the joint articulating surfaces,retracting soft tissue, reaming the humeral canal, and the reaming thegleniod cavity.

The osteotomy cover can be placed on the humerus so that the lip is inposition to prevent a surgical retractor or a reamer from damaging theproximal humerus. Also, this osteotomy protector is size adjustable, itcan be used for bones of varying sizes, while other systems requiremultiple covers to account for patients of different anatomies. Anadjustable protector also saves room in the instrument cases and savesthe surgeon time that would normally be used protecting the resectedsurface.

For example, according to one aspect of the present invention, a coverfor use in protecting a resected surface of a long bone for use in jointarthroplasty is provided. The cover includes a generally planer plane.The body and the member defining a first periphery of the cover when thebody and the member a first position with respect to each other anddefining a second periphery of the cover when the body and the memberare in a second position with respect to each other the second peripherybeing greater than the first periphery. Thus, the present inventionprovides for increasing the overall size of the cover.

The technical advantages of the present invention further include theability to use one cover for varying sizes of anatomies of a resectedsurface of a long bone. For example, according to another aspect of thepresent invention, a cover for use in protecting a resected surface of along bone for use in joint arthroplasty is provided. The cover includesa body and a member moveably attached to the body along a first plane.The moveable member accommodates different size bones. Thus, the presentinvention provides the ability to use one cover for varying sizes ofanatomies of a resected surface of a long bone.

The technical advantages of the present invention include the ability toprevent damage to the long bone, for example, a humerus, to expose theproximal humerus or glenoid while performing the humeral arthroplasty,including exposing the joint articulating surfaces, retracting softtissue, reaming the humeral canal, and the reaming the gleniod cavity.For example, according to yet another aspect of the present invention, acover for use in protecting a resected surface of a long bone for use injoint arthroplasty, for example, in shoulder arthroplasty, is provided.The cover includes a generally planer body having opposed generallyparallel first and second surfaces defining a periphery extending fromthe first surface and the second surface. Thus, the present inventionprovides the ability to prevent damage to the long bone while performingthe humeral arthroplasty, including exposing the joint articulatingsurfaces, retracting soft tissue, reaming the humeral canal, and thereaming the gleniod cavity.

The technical advantages of the present invention further include theability to reduce inventory and size of instrument cases for jointarthroplasty. For example, according to yet another aspect of thepresent invention, a cover for use in protecting a resected surface of along bone for use in joint arthroplasty is provided. The cover includesa body and a member moveable attached to the body along a first plane.The body and the member define a first periphery of the cover when thebody and the member are in a first position with respect to each otherand define a second periphery of the cover when the body and the memberare in a second position with respect to each other. The secondperiphery is greater than the first periphery. Thus, the presentinvention provides the ability to reduce inventory and size ofinstrument cases for joint arthroplasty.

The technical advantages of the present invention further include theability to save surgery time in finding the proper cover for use inprotecting the resected surface of a long bone. For example, accordingto yet another aspect of the present invention, a cover for use inprotecting a resected surface of a long bone for use in jointarthroplasty is provided. The cover includes a body and a membermoveable attached to the body along a first plane. The body and themember define a first periphery of the cover when the body and themember are in a first position with respect to each other and a secondperiphery of the cover when the body and the member are in secondposition with respect to each other. The second periphery being greaterthan the first periphery. Thus, the present invention provides for theability to save surgery time in finding the proper cover for use inprotecting the resected surface of a long bone.

The technical advantage of the present invention further include theability to provide oval and odd shaped covers for resected surfaces foruse in joint arthroplasty. For example, according to yet another aspectof the present invention, a cover for use in protecting a resectedsurface of a long bone for use in joint arthroplasty is provided. Thecover includes a body and a member moveably attached to said body alonga first plane. The body further includes, for example, a second, and maybe a third and fourth member all moveably attachable to the body. Ifthere are four moveable attachable members, the cover may accommodate agreater variety in sizes and shapes of the resected surface of longbones.

Other technical advantages of the present invention will be readilyapparent to one skilled in the art from the following figures,descriptions and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention and theadvantages thereof, reference is now made to the following descriptiontaken in connection with the accompanying drawings, in which:

FIG. 1 is a plan view of a protective cover in position on a humerus inaccordance with an embodiment of the present invention;

FIG. 2 is a plan view of a resected humerus that may be protected withthe protective cover of the present invention;

FIG. 3 is a perspective view of a humeral stem assembly that may beinserted into the resected humerus of FIG. 2 that has been protected bythe protective cover of the present invention;

FIG. 4 is an exploded perspective view of a humeral stem assembly ofFIG. 3;

FIG. 5 is a bottom view of the protective cover of FIG. 1 with themoveable members shown in their extended positions;

FIG. 6 is a bottom view of the protective cover of FIG. 1 with themoveable members shown in their retracted positions;

FIG. 7 is a top view of the protective cover of FIG. 1 with the moveablemembers shown in their extended positions;

FIG. 8 is a top view of the protective cover of FIG. 1 with the moveablemembers shown in their retracted positions;

FIG. 9 is a perspective view of the protective cover of FIG. 1;

FIG. 10 is another perspective view of the protective cover of FIG. 1;

FIG. 11 is a top view of the base of the protective cover of FIG. 1;

FIG. 12 is a cross sectional view of FIG. 11 along the line 12-12 in thedirection of the arrows;

FIG. 13 is a top view of the stud of the protective cover of FIG. 1;

FIG. 14 is a plan view of the stud of FIG. 13;

FIG. 15 is a bottom view of the stud of FIG. 13;

FIG. 16 is a partial view, partially in cross section, of the protectivecover of FIG. 1 showing the stud in greater detail;

FIG. 16A is a partial view, partially in cross section, of anotherembodiment of the protective cover of the present invention utilizing apress fitted stud;

FIG. 16B is a partial view, partially in cross section, of anotherembodiment of the protective cover of the present invention utilizing athreaded stud;

FIG. 17 is a plan view of the third member of the protective cover ofFIG. 1;

FIG. 18 is a bottom view of the third member of FIG. 17;

FIG. 19 is a cross sectional view of FIG. 18 along the line 19-19 in thedirection of the arrows;

FIG. 20 is a plan view of the fourth member of the protective cover ofFIG. 1;

FIG. 21 is a bottom view of the fourth member of FIG. 20;

FIG. 22 is another plan view of FIG. 18 of the fourth member of FIG. 20;

FIG. 23 is a plan view of the first member of the protective cover ofFIG. 1;

FIG. 24 is a bottom view of the first member of FIG. 23;

FIG. 25 is a cross sectional view of FIG. 24 along the line 25-25 in thedirection of the arrows;

FIG. 26 is a plan view of a one piece protective cover in position on ahumerus in accordance with another embodiment of the present invention;

FIG. 27 is a bottom view of a protective cover without a lip in positionon a humerus in accordance with yet another embodiment of the presentinvention;

FIG. 28 is a bottom view of a three piece protective cover in acontracted position in accordance with another embodiment of the presentinvention;

FIG. 29 is a bottom view of the three piece protective cover of FIG. 28in an expanded position;

FIG. 30 is a cross sectional view of FIG. 29 along the line 30-30 in thedirection of the arrows;

FIG. 31 is a bottom view of a protective cover with a spiral guide platein accordance with another embodiment of the present invention;

FIG. 32 is plan view of FIG. 31, partially in cross section; and

FIG. 33 is a flow chart of a method for performing shoulder arthroplastyin accordance with another embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention and the advantages thereof are bestunderstood by referring to the following descriptions and drawings,wherein like numerals are used for like and corresponding parts of thedrawings.

According to the present invention and referring now to FIG. 1, a cover10 for use in protecting a resected surface 12 of a long bone 14 for usein joint arthroplasty is shown. The long bone 14 as shown in FIG. 1 maybe any long bone with a resected surface and may, for example, be in theform of a tibia, a femur, or as is shown in FIG. 1, in the form of ahumerus. The cover 10, as is shown in FIG. 1, includes a body 16 and amember 18 moveably attached to the body 16 along a first plane 20. Thebody 16 and the member 18 define a first periphery 28 of the cover 10when the body 16 and the member 18 are in a first position 30 withrespect to each other. The body 16 and the member 18 define a secondperiphery 32 of the cover 10 when the body 16 and the member 18 are in asecond position 34 with respect to each other, as shown in phantom. Thesecond periphery 34 being greater than the first periphery 28.

Referring now to FIG. 2, a long bone 14 in the form as shown in FIG. 2of a humerus is shown in greater detail. The long bone 14, as is shownin FIG. 2, is resected along resected surface 12 with the head 36 of thelong bone 14 being removed or resected. The removal of the head 36exposes intramedullary canal 38, which, as is shown in FIG. 2, may bereamed or drilled or prepared such that a cavity 40 is formed in thelong bone 14 to prepare the long bone for receiving the prosthesis 42.

Referring now to FIGS. 3 and 4, a trial prosthesis 42 which may befitted into the cavity 40 formed in intramedullary canal 38 of the longbone 14 is shown. The prosthesis 42, as shown in FIGS. 3 and 4, includesa distal stem 44 which defines a pocket 46 in the proximal part of thedistal stem 44. The pocket 46 receives a neck component 48 which issecured to the distal stem 44 by, for example, a fastener 50 in the formof, for example, a screw. A similar implant prosthesis (not shown) mayalso be placed in canal 38.

Referring now to FIGS. 5-10, the cover 10 is shown in greater detail.While the cover 10 may be provided with two components, the body 16 andthe first member 18, it should be appreciated that to provide for awider variety of shapes and sizes for the cover 10 members in additionto the first member 18 may be included in the cover 10.

As shown in FIG. 5, the cover 10 may include a second member 52 which ismoveably attached to the body 16 along first plane 20. The first plane20, as shown in FIG. 5, is in the form or lies along top surface 54 ofthe body 16. As shown in FIG. 5, the first member 18 slides along thetop surface 54 of the body 16 along first plane 20. Similarly, thesecond member 52 slides in first plane 20 along top surface 54 of thebody 16.

The cover 10 may further include a third member 56 which is alsoslideably attached to the body 16 and may, as is shown in FIG. 5, mayextend perpendicularly or transversely to the first member 18 and thesecond member 52. Further, the cover 10 may include a fourth member 58extending outwardly from the body 16 in a direction opposed to the thirdmember 56. As shown in FIG. 5, the cover 10 may assume first position 30forming first periphery 28 along dashed lines 30. Similarly, the firstmember 18, the second member 52, the third member 56, and the fourthmember 58 may form second periphery 32 as shown in solid when the cover10 is in second position 34.

The cover 10 may further include a lip 60 extending from the peripheryof the body 16 or from one of the members, for example, the first member18, the second member 52, the third member 56, or the fourth member 58.As shown in FIG. 5, the lip 60 extends from fourth member 58. The lip 60may, as shown in FIG. 5, extend from the fourth member 58 in a directionnot co-planer with first plane 20. For example and as shown in FIG. 5,the lip may extend perpendicularly or normal to the first plane 20. Asshown in FIG. 5, the cover 10 may further include a protrusion, forexample, first protrusion 62 extending from first member 18.

While the first periphery 28 and the second periphery 32 may have anysuitable shape, it should be appreciated that the cover 10 preferablyhas a shape to conform to that of the resected surface of the long bone.For example, the cover 10 may have a first periphery 28 and a secondperiphery 32 that are each arcuate.

It should be appreciated that the sliding members may be connected tothe cover 10 in any suitable fashion. For example and as shown in FIG.5, the body 16 may include a first slot 64 which may extend radiallyoutward from center or origin 22 of the body 16. The first slot 64 maybe adapted to receive a first stud 66 which is fixedly secured to firstmember 18. The first stud 66 may include a head 68 as well as a body 70having an oval cross section. The body 70 may have a width WS which ismatingly fitted to width W of the first slot 64. The stud 66 serves toguide the first member 18 radially inward and outwardly from the origin22 to position the first member 18 with respect to the body 16, to sucha place as is suitable for use with the particular resected surface ofthe long bone.

Similarly, and as shown in FIG. 5, the body 16 may include a second slot72 to which a second stud 74 rigidly secured to the second member 52slideably fits. The second stud 74 is rigidly secured to the secondmember 52 to permit the second member 52 to move radially outward fromorigin 22 of the body 16. The body 16 may similarly include a third slot76 which slideably receives a third stud 78 which is rigidly secured tothe third member 56. The third stud 78 is slideably fitted within thethird slot 76 to permit the third member 56 to move radially outwardfrom origin 22 of the body 16.

Similarly, the body 16 may similarly include a fourth slot 80 whichslideably receives a fourth stud 82 which is rigidly secured to thefourth member 58. The slot 80 serves to permit the fourth member 58 tomove radially outward from origin 22 of the body 16.

Referring now to FIG. 6, the cover 10 is shown with the members 18, 52,56 and 58 in first position 30. The cover 10, as shown in FIG. 6,includes body 16 as well as first member 18, second member 52, thirdmember 56, and fourth member 58. The first member 18 and the secondmember 52 slideably fit against the body 16. For example, and as isshown in FIGS. 6 and 7, the body 16 includes an inner face 24 to whichouter face 86 of the first member 18 slideably fits. Similarly, thesecond member 52 includes an outer face 91 which slides along inner face24 of the body 16.

The third member 56 includes outer face 15 which slides against innerface 88 of the first member 18 and the inner face 92 of the secondmember 52. Similarly, the fourth member 58 includes an outer face 93which slideably fits against the inner face 88 of the first member 18and against the inner face 92 of the second member 52.

The first member 18 includes a land 94 which provides an inner limit tothe movement of the third member 56 and the fourth member 58. Similarly,the second member 52 includes a land 95 which serves as an innermovement limit for the third member 56 and the fourth member 58.

While the body 16, the first member 18, the second member 52, the thirdmember 56, and the fourth member 58 may have any suitable shape,preferably the body and members have a periphery that is arcuate, forexample, a periphery that is a portion of a circle. For example and asshown in FIG. 6, the periphery of the body 16 is defined by a radius RBextending from origin 22. Similarly, the periphery of the first member18 is defined by a radius R1M extending from origin 22. The secondmember periphery is defined by a radius R2M extending from origin 22.Similarly, the third member 56 has a periphery defined by radius R3Mextending from origin 22. The fourth member 58 has a periphery definedby radius R4M extending from origin 22.

The lip 60 includes a shape that may be defined as arcuate and may bedefined by radius RO extending from origin 22 and a radius RI extendingfrom origin 22.

Referring now to FIGS. 7 and 8, the cover 10 is shown with the coverturned 180° with top surface 96 of the body 16 showing on top.

Referring now to FIGS. 9 and 10, the cover 10 is shown in a perspectiveview.

Referring now to FIGS. 11 and 12, the body 16 of the cover 10 is shownin greater detail. The body 16 has a generally cylindrical shape and isdefined by radius RB extending from origin 22. The body 16 also has athickness TB appropriately chosen. The body 16 includes a plurality ofslots, each slot having a slot width WSL and a slot length LSL. Thewidth WSL and the length LSL are chosen to mate with the studs, forexample, the first stud 66 which should be similar to the second stud74, the third 78, and the fourth stud 82.

As shown in FIG. 11, the first slot 64 extends radially outward fromorigin 22. The second slot 72 is opposed to the first slot 64. The thirdslot 76 and the fourth slot 80 are normal or perpendicular to the firstslot 64 and the second slot 72.

Referring now to FIGS. 13, 14 and 15, the studs of the cover 10 of thepresent invention are shown in greater detail. The first stud 66 isshown in FIGS. 13, 14, and 15. It should be appreciated that the secondstud 74, the third 78, and the fourth stud 82 are, for simplicity,identical to the first stud 66. As such, the first stud 66 will bedescribed in FIGS. 13, 14 and 15. The stud 66 includes the head 68 whichextends from an end of body 70. The head 38 is cylindrical and isdefined by head diameter HD and head thickness HT. The body 70 isdefined by a body height BH and is oval defined by a width WST and alength LST. It should be appreciated that the width WST and length LSTare selected to matingly fit with the slots 64, 72 76, and 80 of thebody 16 of the cover 10.

The studs 66, 74, 78, and 82 may be secured to the respective members18, 52, 56, and 58 in any suitable fashion. For example, the studs maybe interferencely fitted, welded, or threadably secured to the othercomponents of the cover 10.

Referring now to FIG. 16, for example the first stud 66 is welded withwelding material 13 to first member 18.

Referring now to FIG. 16A, an alternate embodiment of the presentinvention is shown as cover 10A. The cover 10 A includes a stud 66A thatis press fitted to first member 18A.

Referring now to FIG. 16B, another alternate embodiment of the presentinvention is shown as cover 10B. The cover 10 A includes, for example, afirst member 18B to which stud 66B is threadably engaged.

Referring now to FIGS. 17, 18, and 19, the third member 56 of the cover10 is shown in greater detail. The third member 56 has a generallysemi-cylindrical shape and has a thickness T3M as well as a radius R3Mextending from origin 22. The third member 56 defines the outer face 15and an opposed parallel inner face 87. The third member further definesa land 89 extending outwardly centrally from outer face 15 and isdefined by a thickness T3L and a width W3.

The third member 56 may further include a protrusion 19 extendingoutwardly from inner face 87 for engagement with the resected face ofthe long bone 14.

The third member 56 may further include an oblong opening 96 centrallylocated in the third member 56 and extending from outer face 15 throughinner face 87. The oblong opening 96 is adapted to receive the thirdstud 78 and thus has a width WTS and a length LSL.

Referring now to FIGS. 20, 21, and 22, the fourth member 58 is shown ingreater detail. The fourth member 58 has a generally semi-cylindricalshape defined by a thickness T4M and a radius R4M extending from origin22. The fourth member 58 includes a lip 60 extending outwardly frominner face 97 of the fourth member 58. The inner face 97 and the outerface 93 define a thickness T4M there between. The fourth member 58further includes a land 98 extending outwardly from outer face 93 anddefined by a thickness T4L and a width W4L.

The fourth member 58 further includes an oblong opening 99 centrallylocated and extending from the inner face 97 to the outer face 93 of thefourth member 58. The oblong opening 99 is defined by, for example, awidth WSL and a length LSL corresponding to the dimensions of the fourthstud 82.

The fourth member 58 further includes a protrusion 21 extending inwardlyfrom inner face 97.

Referring now to FIGS. 22 and 23, the lip 60 may be defined, forexample, by lip width LW and by lip thickness LT. The lip 60 may furtherbe defined by an angle α extending from first end 23 to second end 25 ofthe lip 60.

Referring now to FIGS. 23, 24, and 25, the first member 18 is shown ingreater detail. It should be appreciated that the first member 18 andthe second member 52 may be identical to each other. Thus, FIGS. 23, 24,and 25 are used to describe first member 18, but may also describe thesecond member 52. The first member 18 may further include a protrusion62 extending outwardly from inner face 88 for engagement with theresected face of the long bone 14.

The first member 18 has a generally semi-cylindrical shape and isdefined by thickness T1M and radius R1M extending from origin 22. Thefirst member 18 includes the inner face 88 and an opposed parallel outerface 26. The land 94 of the first member 18 extends from inner face 88.A first protrusion 62 also extends outwardly from land 94 of the firstmember 18. The first member 18 further includes a first member oblongopening 84 extending from inner face 88 to outer face 26. The oblongopening 84 has a slot length LSL and a slot width WSL to mate with thedimensions of first stud 66.

Referring now to FIG. 26, yet another embodiment of the presentinvention is shown as cover 110. The cover 110 is simpler than the cover10 of FIGS. 1-25 in that the cover 110 is unitary or made of a one-pieceor integral construction. The cover 110 includes a generally cylindricalplaner body portion 116 as well as a lip 160 that extends outwardly fromperiphery 128 of the planer body portion 116.

Referring now to FIG. 27, yet another embodiment of the presentinvention is shown as cover 210. The cover 210 is very similar to thecover 10 of FIGS. 1-25 except the cover 210 of FIG. 27 does not includea lip. The cover 210 includes a body 216 similar to the body 16 of thecover 10 of FIGS. 1-25. The cover 210 further includes a first member218 similar to the first member 18 of the cover 10 and a second member252 similar to the second member 52 of the cover 10 of FIGS. 1-25.

The cover 210 further includes a third member 256 similar to the thirdmember 56 of the cover 10 of FIGS. 1-25 and a fourth member 258 similarto the fourth member 58 of the cover 10 of FIGS. 1-25. The cover 210further includes slots such as slots 264 similar to slots 64 of thecover 10 and studs 266 which are fitted to the slots 264 to permit themembers to mover relative the body 216.

Referring now to FIGS. 28, 29 and 30, yet another embodiment of thepresent invention is shown as cover 310. The cover 310 is quite simpleand includes only three pieces. The cover 310 includes a body 316 havinga generally circular disc shape and an opening 364 positioned off-centeron the body 316. The cover 310 further includes a first member 318 whichhas a cylindrical disc shape similar to that of the body 316 and a stud366 is rigidly secured off-center by welding material 313 from firstface 326 of the first member 318. The stud 366 is pivotally secured tothe opening 364 in the body 316 to rotatably secure the first member 318to the body 316 to form the cover 310. The cover 310 may further includethe lip 360 which may be secured to the body 316 and extend in adirection opposed to that of the first member 318.

Referring now to FIGS. 28 and 29, the cover 310 is in a first position306 as shown in FIG. 28 when the first member 318 and the body 316 arein alignment with each other. As shown in FIG. 29, the cover 310 is in asecond position 308 when the first member 318 is out of alignment withthe body 316.

Referring now to FIGS. 31 and 32, yet another embodiment of the presentinvention is shown as cover 410. The cover 410 is similar to the cover10 of FIGS. 1-25 except that the cover 410 includes an additionalcomponent in the form of an actuator 433 which is positioned againstbody 416 and may be rotatably secured to the body 416 by a stud 435 thatis rigidly secured to the body 416 and rotatably secured through opening437 formed in the actuator 433. The actuator 433 may include arcuateslots 439 which slideably receive the heads 468 of the studs 466 suchthat as the actuator 433 is rotated in the direction of arrow 408, thestuds 466 are forced outwardly thereby forcing the members 418, 452,456, and 458 outwardly in a similar fashion to provide a simple andquick method of actuating and adjusting the cover 410.

Referring now to FIG. 33, yet another embodiment of the presentinvention is shown as surgical procedure or method 500. The methodincludes a first step 510 of resecting the long bone and a second step512 of providing a cover including a first portion and a second portionthe second portion moveable with respect to the first portion. Themethod also includes a third step 514 of placing the cover over theresected end of the long bone and a fourth step 516 of adjusting thecover to fit the resected end of the long bone. The method also includesa fifth step 518 of securing the cover to the resected end of the longbone.

Although the present invention and its advantages have been described indetail, it should be understood that various changes, substitutions, andalterations can be made therein without departing from the spirit andscope of the present invention as definite by the appended claims.

What is claimed is:
 1. A cover for use in protecting a resected surfaceof a long bone for use in joint arthroplasty, comprising: a body; aplurality of independently moveable members moveably attached to thebody, two of the plurality of independently movable members configuredto move linearly with respect to the body along a first plane and alonga first axis, the body and the plurality of independently moveablemembers having a first configuration and a second configuration, thefirst configuration defining a first periphery of the cover along thefirst plane, the second configuration defining a second periphery of thecover along the first plane, wherein the first periphery encompasses afirst area when projected onto the first plane and the second peripheryencompasses a second area when projected onto the first plane, thesecond area larger than the first area and including all of the firstarea; and a lip fixedly extending downwardly along an outer radialperiphery of one of the body and the plurality of independently moveablemembers in a direction not co-planar with the first plane, the liphaving an inwardly facing portion, the inwardly facing portionconfigured such that when the cover is positioned on the resectedsurface of the long bone, the inwardly facing portion can abut a surfaceof the long bone extending about the resected surface.
 2. The cover ofclaim 1, wherein: the plurality of independently moveable members andthe body form a continuous barrier along the first plane within thefirst periphery in the first configuration; and the plurality ofindependently moveable members and the body form a substantiallycontinuous barrier along the first plane within the second periphery inthe second configuration.
 3. The cover of claim 1, wherein the lipextends generally normal to the first plane.
 4. The cover of claim 1,further comprising a protrusion extending downwardly from at least oneof the plurality of independently moveable members and configured forinsertion into a bone.
 5. The cover of claim 1, wherein a periphery ofat least one of the body and the plurality of independently moveablemembers is arcuate along the first plane.
 6. The cover of claim 1,wherein: the inwardly facing portion is defined by a first radius ofcurvature; the lip includes an outwardly facing portion defined by asecond radius of curvature; and the second radius of curvature isgreater than the first radius of curvature.
 7. The cover of claim 1,wherein the lip fixedly extends downwardly at the outer radial peripheryof the body.
 8. A cover for use in protecting a resected surface of along bone for use in joint arthroplasty, comprising: a body; a pluralityof independently moveable members moveably attached to the body, two ofthe plurality of independently movable members configured to movelinearly with respect to the body along a first plane and along a firstaxis, the body and the plurality of independently moveable membersdefining a first periphery of the cover along the first plane when thebody and the plurality of independently moveable members are in a firstposition with respect to each other and defining a second periphery ofthe cover along the first plane when the body and the plurality ofindependently moveable members are in a second position with respect toeach other, wherein the first periphery encompasses a first area whenprojected onto the first plane and the second periphery encompasses asecond area when projected onto the first plane, and the second area islarger than the first area and includes all of the first area; and a lipfixedly extending downwardly along an outer radial periphery of one ofthe body and the plurality of independently moveable members in adirection not co-planar with the first plane, the lip having an inwardlyfacing portion, the inwardly facing portion configured such that whenthe cover is positioned on the resected surface of the long bone, theinwardly facing portion can abut a surface of the long bone extendingabout the resected surface.
 9. The cover of claim 8, wherein the lipextends generally normal to the first plane.
 10. The cover of claim 8,further comprising a protrusion extending downwardly from at least oneof the plurality of independently moveable members and configured forinsertion into a bone.
 11. The cover of claim 8, wherein a periphery ofat least one of the body and the plurality of independently moveablemembers is arcuate along the first plane.
 12. The cover of claim 8,wherein the plurality of independently moveable members comprises: afirst member moveably attached to the body; and a second member moveablyattached to the body, the second member opposed to the first member. 13.The cover of claim 12, wherein the body defines a first internal walldefining a first slot and a second internal wall defining a second slot,the cover further comprising: a first guide connected to the firstmember, the first guide slideably fitted to the first slot; and a secondguide connected to the second member, the second guide slideably fittedto the second slot.
 14. The cover of claim 13, wherein: the first slotdefines a first longitudinal axis; the second slot defines a secondlongitudinal axis; and the first longitudinal axis and the secondlongitudinal axis are collinear.
 15. The cover of claim 14, wherein: thebody defines a third internal wall defining a third slot and a fourthinternal wall defining a fourth slot; the plurality of independentlymoveable members further comprises a third member moveably attached tothe body, the third member moveable along a second axis perpendicular tothe first longitudinal axis; the plurality of independently moveablemembers further comprises a fourth member moveably attached to the body,the fourth member opposed to the third member; the cover furthercomprises a third guide connected to the third member, the third guideslideably fitted to the third slot; and the cover further comprises afourth guide connected to the fourth member, the fourth guide slideablyfitted to the fourth slot.
 16. The cover of claim 8, wherein the bodydefines a first internal wall defining a slot, the cover furthercomprising: a first guide connected to a first of the plurality ofindependently moveable members, the guide including a body with an ovalcross section slideably fitted to the slot.
 17. The cover of claim 8,wherein: the plurality of independently moveable members and the bodyform a continuous barrier along the first plane within the firstperiphery in the first position; and the plurality of independentlymoveable members and the body form a substantially continuous barrieralong the first plane within the second periphery in the secondposition.
 18. The cover of claim 8, wherein: the inwardly facing portionis defined by a first radius of curvature; the lip includes an outwardlyfacing portion defined by a second radius of curvature; and the secondradius of curvature is greater than the first radius of curvature. 19.The cover of claim 8, wherein the lip fixedly extends downwardly at theouter radial periphery of the plurality of independently moveablemembers.